[CraigS]

Here's an interesting article which clearly demonstrates an example of where chaos theory and fractal geometry has been used successfully in a geological field of study. The study topic was growth of rock features at Angel Terrace, Mammoth Hot Springs in Yellowstone National Park.

Although the rock motifs may look randomly arranged by precipitation, scientists are continually discovering more patterns to the growth formations. In the past, scientists thought that the rock architecture surrounding calcium carbonate springs (either hot or cold) could only be explained by detailed analysis of the crystal structure, water chemistry, and perhaps the metabolic activity of the microbes that populate the spring water.

Now, scientists from the University of Illinois suggest that large scale structures near hot springs can be understood using a simple, generic model based that depends not on such specific details, but rather on broad physical principles such as the dynamics of fluids, precipitation and crystal growth.

“Earlier work [on rock growth] has concentrated on much smaller length scales, trying to understand the crystal morphology, and so on,” Goldenfeld told PhysOrg.com. “I don't think many people thought about trying to understand the whole landscape: at first sight it seems impossible!”
...
“Our preliminary simulations indicate that at least some statistical measures of the landscapes, such as the pond size distribution function, are fractal,” they conclude in the paper. Goldenfeld also added that a following paper, which is being readied for publication, has gone “well beyond the speculations” in this paper, and that “the modeling approach works spectacularly well.”

Clearly, this is a case where looking for the fractality in the landscape advanced the study dramatically. The study went on to develop the understanding of how living organisms are effected by the changing environment.

Horse for courses ? Of course .. I have no problems with that.

Here's another one where the CSIRO figured out a way to improve the in-situ leaching process to extract ore deposits:

"What is needed is a way to ‘stir’ the {leaching} solution while it is underground and that’s where chaos theory comes into the equation."

My point is simply that wherever chaos thinking and fractal geometry perspectives are included in the study of natural phenomena (including geology/geophysics, etc), large advances in understanding are reported. Deterministic predictions may, (or may not) be possible at certain scales, but this is not the only goal of adopting a broadened outlook, which different perspectives offer.

When comparing the invocation of planet-wide catastrophes, (which should be the last alternative), versus simply confronting the possibility of unpredictability offered by chaos thinking, the evidence is in such cases, that greater advances in understanding can be achieved by adopting the chaos perspectives, and this is commonplace within mainstream scientific models.

There are many, many other such case examples from the geological sciences.

Cheers